Western blot analysis of Strep-Tag II in different lysates. Proteins were transferred to a PVDF membrane and blocked with 5% BSA in PBS for 1 hour at room temperature. Samples were incubated in Strep-Tag II Monoclonal antibody (Product # MA5-44988) using a dilution of 1:1,000 in 5% BSA at room temperature for 2 hours followed by Goat Anti-Mouse IgG - HRP secondary antibody at a dilution of 1:5,000 for 1 hour at room temperature. Positive control: Lane 1: Strep-Tag II protein transfected 293F cells lysate; Lane 2: Non-transfected 293F cells lysate.